Physical Fitness Is Directly Related to Exercise Capacity and Ventilatory Response to Exercise in Men with HFrEF.

: Heart failure (HF) patients experience reduced functional fitness level (determining the performance of routine, daily activities) and diminished exercise capacity (linked to more effortful activities). : The aim of the study is to assess this relationship using functional fitness tests compared to peak VO2 and VE/VCO2 slope in the context of exercise capacity and ventilatory response to exercise. : A total of 382 men with stable HFrEF (age: 61 ± 10, NYHA class I/II/III/IV: 16/50/32/2%, LVEF: 30.